Scanning Imaging Absorption Spectrometer for Atmospheric Chartography carbon monoxide total columns: Statistical evaluation and comparison with chemistry transport model results

Abstract. Despite the recently reported beginning of a recovery in global stratospheric ozone (O3), an unexpected O3 decline in the tropical mid-stratosphere (around 30–35 km altitude) was observed in satellite measurements during the first decade of the 21st century. We use SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) measurements for the period 2004–2012 to confirm the significant O3 decline. The SCIAMACHY observations show that the decrease in O3 is accompanied by an increase in NO2. To reveal the causes of these observed O3 and NO2 changes, we performed simulations with the TOMCAT 3-D chemistry-transport model (CTM) using different chemical and dynamical forcings. For the 2004–2012 time period, the TOMCAT simulations reproduce the SCIAMACHY-observed O3 decrease and NO2 increase in the tropical mid-stratosphere. The simulations suggest that the positive changes in NO2 (around 7 % decade−1) are due to similar positive changes in reactive odd nitrogen (NOy), which are a result of a longer residence time of the source gas N2O and increased production via N2O + O(1D). The model simulations show a negative change of 10 % decade−1 in N2O that is most likely due to variations in the deep branch of the Brewer–Dobson Circulation (BDC). Interestingly, modelled annual mean “age of air” (AoA) does not show any significant changes in transport in the tropical mid-stratosphere during 2004–2012. However, further analysis of model results demonstrates significant seasonal variations. During the autumn months (September–October) there are positive AoA changes that imply transport slowdown and a longer residence time of N2O allowing for more conversion to NOy, which enhances O3 loss. During winter months (January–February) there are negative AoA changes, indicating faster N2O transport and less NOy production. Although the variations in AoA over a year result in a statistically insignificant linear change, non-linearities in the chemistry–transport interactions lead to a statistically significant negative N2O change.

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A 60 yr record of atmospheric carbon monoxide reconstructed from Greenland firn air

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-7567-2013 ◽

2013 ◽

Vol 13 (15) ◽

pp. 7567-7585 ◽

Cited By ~ 19

Author(s):

V. V. Petrenko ◽

P. Martinerie ◽

P. Novelli ◽

D. M. Etheridge ◽

I. Levin ◽

...

Keyword(s):

Carbon Monoxide ◽

Transport Model ◽

Ice Core ◽

Emission Inventories ◽

Road Transportation ◽

Atmospheric Measurements ◽

Chemistry Transport Model ◽

Atmospheric Carbon ◽

Atmospheric Carbon Monoxide ◽

Co Emission

Abstract. We present the first reconstruction of the Northern Hemisphere (NH) high latitude atmospheric carbon monoxide (CO) mole fraction from Greenland firn air. Firn air samples were collected at three deep ice core sites in Greenland (NGRIP in 2001, Summit in 2006 and NEEM in 2008). CO records from the three sites agree well with each other as well as with recent atmospheric measurements, indicating that CO is well preserved in the firn at these sites. CO atmospheric history was reconstructed back to the year 1950 from the measurements using a combination of two forward models of gas transport in firn and an inverse model. The reconstructed history suggests that Arctic CO in 1950 was 140–150 nmol mol−1, which is higher than today's values. CO mole fractions rose by 10–15 nmol mol−1 from 1950 to the 1970s and peaked in the 1970s or early 1980s, followed by a ≈ 30 nmol mol−1 decline to today's levels. We compare the CO history with the atmospheric histories of methane, light hydrocarbons, molecular hydrogen, CO stable isotopes and hydroxyl radicals (OH), as well as with published CO emission inventories and results of a historical run from a chemistry-transport model. We find that the reconstructed Greenland CO history cannot be reconciled with available emission inventories unless unrealistically large changes in OH are assumed. We argue that the available CO emission inventories strongly underestimate historical NH emissions, and fail to capture the emission decline starting in the late 1970s, which was most likely due to reduced emissions from road transportation in North America and Europe.

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Sensitivity of chemistry-transport model simulations to the duration of chemical and transport operators: a case study with GEOS-Chem v10-01

Geoscientific Model Development ◽

10.5194/gmd-9-1683-2016 ◽

2016 ◽

Vol 9 (5) ◽

pp. 1683-1695 ◽

Cited By ~ 17

Author(s):

Sajeev Philip ◽

Randall V. Martin ◽

Christoph A. Keller

Keyword(s):

Carbon Monoxide ◽

Nitrogen Oxides ◽

Spatial Resolution ◽

Transport Model ◽

Transport Models ◽

Chemistry Transport Model ◽

Simulation Accuracy ◽

Transport Operator ◽

Computational Expense ◽

Simulation Error

Abstract. Chemistry-transport models involve considerable computational expense. Fine temporal resolution offers accuracy at the expense of computation time. Assessment is needed of the sensitivity of simulation accuracy to the duration of chemical and transport operators. We conduct a series of simulations with the GEOS-Chem chemistry-transport model at different temporal and spatial resolutions to examine the sensitivity of simulated atmospheric composition to operator duration. Subsequently, we compare the species simulated with operator durations from 10 to 60 min as typically used by global chemistry-transport models, and identify the operator durations that optimize both computational expense and simulation accuracy. We find that longer continuous transport operator duration increases concentrations of emitted species such as nitrogen oxides and carbon monoxide since a more homogeneous distribution reduces loss through chemical reactions and dry deposition. The increased concentrations of ozone precursors increase ozone production with longer transport operator duration. Longer chemical operator duration decreases sulfate and ammonium but increases nitrate due to feedbacks with in-cloud sulfur dioxide oxidation and aerosol thermodynamics. The simulation duration decreases by up to a factor of 5 from fine (5 min) to coarse (60 min) operator duration. We assess the change in simulation accuracy with resolution by comparing the root mean square difference in ground-level concentrations of nitrogen oxides, secondary inorganic aerosols, ozone and carbon monoxide with a finer temporal or spatial resolution taken as “truth”. Relative simulation error for these species increases by more than a factor of 5 from the shortest (5 min) to longest (60 min) operator duration. Chemical operator duration twice that of the transport operator duration offers more simulation accuracy per unit computation. However, the relative simulation error from coarser spatial resolution generally exceeds that from longer operator duration; e.g., degrading from 2°  ×  2.5° to 4°  ×  5° increases error by an order of magnitude. We recommend prioritizing fine spatial resolution before considering different operator durations in offline chemistry-transport models. We encourage chemistry-transport model users to specify in publications the durations of operators due to their effects on simulation accuracy.

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Source attribution of carbon monoxide and ozone over the Indian subcontinent using MOZART-4 chemistry transport model

Atmospheric Research ◽

10.1016/j.atmosres.2019.04.019 ◽

2019 ◽

Vol 227 ◽

pp. 165-177 ◽

Cited By ~ 3

Author(s):

Yesobu Yarragunta ◽

Shuchita Srivastava ◽

D. Mitra ◽

Eric Le Flochmoën ◽

Brice Barret ◽

...

Keyword(s):

Carbon Monoxide ◽

Transport Model ◽

Indian Subcontinent ◽

Source Attribution ◽

Chemistry Transport Model

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Supplementary material to "Calibrating a global atmospheric chemistry transport model using Gaussian process emulation and ground-level concentrations of ozone and carbon monoxide"

10.5194/gmd-2021-39-supplement ◽

2021 ◽

Author(s):

Edmund Ryan ◽

Oliver Wild

Keyword(s):

Carbon Monoxide ◽

Gaussian Process ◽

Atmospheric Chemistry ◽

Transport Model ◽

Ground Level ◽

Chemistry Transport Model ◽

Gaussian Process Emulation ◽

Supplementary Material

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Dynamically controlled ozone decline in the tropical mid-stratosphere observed by SCIAMACHY

10.5194/acp-2018-746 ◽

2018 ◽

Author(s):

Evgenia Galytska ◽

Alexey Rozanov ◽

Martyn P. Chipperfield ◽

Sandip S. Dhomse ◽

Mark Weber ◽

...

Keyword(s):

Residence Time ◽

Transport Model ◽

Stratospheric Ozone ◽

Satellite Measurements ◽

Chemistry Transport Model ◽

Deep Branch ◽

Negative Change ◽

Time Period ◽

Scanning Imaging ◽

Odd Nitrogen

Abstract. Despite the recently reported beginning of a recovery in global stratospheric ozone (O3), an unexpected O3 decline in the tropical mid-stratosphere (around 30–35 km altitude) was observed in satellite measurements during the first decade of the 21st century. We use SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) measurements for the period 2004–2012 to confirm the significant O3 decline. The SCIAMACHY observations also show that the decrease in O3 is accompanied by an increase in NO2. To reveal the causes of these observed O3 and NO2 changes, we performed simulations with the TOMCAT 3D Chemistry-Transport Model (CTM) using different chemical and dynamical forcings. For the 2004–2012 time period, the TOMCAT simulations reproduce the SCIAMACHY-observed O3 decrease and NO2 increase in the tropical mid-stratosphere. The simulations suggest that the positive changes in NO2 (around 7 % per decade) are due to similar positive changes in reactive odd nitrogen (NOy), which are a result of a longer residence time of the source gas N2O and increased production via N2O + O(1D). The model simulations show a negative change of 10 % per decade in N2O that is most likely due to variations in the deep branch of the Brewer-Dobson Circulation (BDC). Interestingly, modelled annual mean age-of-air (AoA) does not show any significant changes in the transport in the tropical mid-stratosphere during 2004–2012. However, further analysis of model results demonstrate significant seasonal variations. During the autumn months (September–October) there are positive AoA changes, that imply transport slowdown and a longer residence time of N2O allowing larger conversion to NOy which enhances O3 loss. During winter months (January–February) there are negative AoA changes, indicating faster N2O transport and less NOy production. Although the changes in AoA cancel out when averaging over the year, non-linearities in the chemistry-transport interactions mean that the net negative N2O change remains.

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On the consistency between global and regional methane emissions inferred from SCIAMACHY, TANSO-FTS, IASI and surface measurements

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-577-2014 ◽

2014 ◽

Vol 14 (2) ◽

pp. 577-592 ◽

Cited By ~ 51

Author(s):

C. Cressot ◽

F. Chevallier ◽

P. Bousquet ◽

C. Crevoisier ◽

E. J. Dlugokencky ◽

...

Keyword(s):

Near Infrared ◽

Transport Model ◽

Methane Emissions ◽

Chemistry Transport Model ◽

Satellite Retrievals ◽

Surface Measurements ◽

Scanning Imaging ◽

One Year ◽

The One ◽

Global Emissions

Abstract. Satellite retrievals of methane weighted atmospheric columns are assimilated within a Bayesian inversion system to infer the global and regional methane emissions and sinks for the period August 2009 to July 2010. Inversions are independently computed from three different space-borne observing systems and one surface observing system under several hypotheses for prior-flux and observation errors. Posterior methane emissions are compared and evaluated against surface mole fraction observations via a chemistry-transport model. Apart from SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY), the simulations agree fairly well with the surface mole fractions. The most consistent configurations of this study using TANSO-FTS (Thermal And Near infrared Sensor for carbon Observation – Fourier Transform Spectrometer), IASI (Infrared Atmospheric Sounding Interferometer) or surface measurements induce posterior methane global emissions of, respectively, 565 ± 21 Tg yr−1, 549 ± 36 Tg yr−1 and 538 ± 15 Tg yr−1 over the one-year period August 2009–July 2010. This consistency between the satellite retrievals (apart from SCIAMACHY) and independent surface measurements is promising for future improvement of CH4 emission estimates by atmospheric inversions.

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Assimilation of carbon monoxide measured from satellite in a three-dimensional chemistry-transport model

Journal of Geophysical Research Atmospheres ◽

10.1029/2000jd900682 ◽

2001 ◽

Vol 106 (D14) ◽

pp. 15385-15394 ◽

Cited By ~ 25

Author(s):

Cathy Clerbaux ◽

Juliette Hadji-Lazaro ◽

Didier Hauglustaine ◽

Gérard Mégie ◽

Boris Khattatov ◽

...

Keyword(s):

Carbon Monoxide ◽

Transport Model ◽

Three Dimensional ◽

Chemistry Transport Model

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A 60-yr record of atmospheric carbon monoxide reconstructed from Greenland firn air

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-18993-2012 ◽

2012 ◽

Vol 12 (8) ◽

pp. 18993-19037 ◽

Cited By ~ 2

Author(s):

V. V. Petrenko ◽

P. Martinerie ◽

P. Novelli ◽

D. M. Etheridge ◽

I. Levin ◽

...

Keyword(s):

Carbon Monoxide ◽

Transport Model ◽

Ice Core ◽

Emission Inventories ◽

Road Transportation ◽

Atmospheric Measurements ◽

Chemistry Transport Model ◽

Atmospheric Carbon ◽

Atmospheric Carbon Monoxide ◽

Co Emission

Abstract. We present a reconstruction of the Northern Hemisphere (NH) high latitude atmospheric carbon monoxide (CO) mole fraction from Greenland firn air. Firn air samples were collected at three deep ice core sites in Greenland (NGRIP in 2001, Summit in 2006 and NEEM in 2008). CO records from the three sites agree well with each other as well as with recent atmospheric measurements, indicating that CO is well preserved in the firn at these sites. CO atmospheric history was reconstructed back to the year 1950 from the measurements using a combination of two forward models of gas transport in firn and an inverse model. The reconstructed history suggests that Arctic CO was already higher in 1950 than it is today. CO mole fractions rose gradually until the 1970s and peaked in the 1970s or early 1980s, followed by a decline to today's levels. We compare the CO history with the atmospheric histories of methane, light hydrocarbons, molecular hydrogen, CO stable isotopes and hydroxyl radical (OH), as well as with published CO emission inventories and results of a historical run from a chemistry-transport model. We find that the reconstructed Greenland CO history cannot be reconciled with available emission inventories unless large changes in OH are assumed. We argue that the available CO emission inventories chronically underestimate NH emissions, and fail to capture the emission decline starting in the late 1970s, which was most likely due to reduced emissions from road transportation in North America and Europe.

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